Delhi air pollution: What kind of a challenge is stubble-burning? The crisis decoded

Every year, the onset of winter in Delhi unfailingly brings to the fore the burning of paddy residue in Punjab and Haryana, given the practice contributes significantly to the national capital's air pollution woes, with severe consequences for public health. According to an IIT study, 17% of the PM 10 load and 26% of the PM 2.5 load in October-November in Delhi can be attributed to post-monsoon crop residue burning in these states. In addition to increasing atmospheric load of particulate matter in situ and in neighbouring regions, biomass burning also contributes to greenhouse gas emissions and destroys soil ecosystems.

Paddy residue burning in the western Indo-Gangetic plain has continued to expand over the years. It has become the norm in more or less the entire farming community of Punjab, the granary of India. Despite the measures being undertaken by various authorities over many years, between 80-90% of the paddy residue generated in the state (close to 20 million tonnes) is burnt. While still problematic, the scales of residue production and burning in Haryana and western Uttar Pradesh are significantly lower. As such, there is a need for a deeper and nuanced understanding of the issue so that the root causes of the problem are identified and pathways to mitigate this phenomenon are located.

In Punjab, paddy cultivation-introduced during the Green Revolution (GR) for addressing food security needs-grew exponentially, underpinned by massive institutional support by the state including assured price and marketing support. The population of the Indo-Gangetic plain is not one that consumes copious quantities of rice; thus, the rice-wheat rotation which currently occupies nearly 80% of the total cropped area in Punjab displaced other traditional crops more suited to the region. While the GR has led to self-sufficiency in food-grains (rice and wheat), the near complete focus on productivity had unintended ecological and socioeconomic repercussions on Punjab's agrarian community. The mono-cropping of rice has led to a massive depletion of the water table and, given the double-cropping with wheat, it has led to loss of soil fertility and biodiversity, excessive use of chemical fertilisers and pesticides, and water pollution. In parallel, along with the ecological degradation, the region has been witnessing stagnation in yields, rising input usage and costs in the absence of incremental returns, rural indebtedness and prevalence of serious health problems (which, while contested, is attributed to exposure to high input use, by some experts). This has culminated in the well-known agrarian crisis of India's granary. Paddy residue burning is a one facet of the crisis in that region.

Farmers resort to the annual burning of paddy stubble and straw given the short window available for them to harvest paddy and prepare the field for sowing the successive wheat crop. Since the advent of mechanised farming and growing labour shortage in the region, combined harvestors are used to harvest paddy which leave large quantities of stubble and straw as residue on the fields. Given time constraints, problems with storing, in-field use and off- field disposal of the residue, farmers burn it to clear the field quickly and inexpensively. As many interested in addressing this problem will tell you, paddy residue burning is as much a socioeconomic challenge as it is one of technology improvisation.

Clearly, there is a need to rethink agriculture policy, innovation & practice and institutional roles in Punjab if one is serious about addressing paddy residue burning. Another important area is crop residue management. There are various on-field (soil incorporation of residue to improve soil health) and off-field disposal options (biomass based power generation, biogas and co-generation of fertilizer, mushroom beds, paper/cardboard making and packaging; others like bioethanol production are in the pipeline) for paddy residue management. Whereas straw Management Systems and Happy Seeder technologies have appeared as on-field residue management options, using paddy residue for clean energy appears as a promising off-field option. However, analysis of the technical performance and cost-benefit economics of the on-field options, as well as techno-commercial viability of the off-field options is necessary. Examining how supply-chains can be organised to cater to these options is as crucial as identifying sustainable business models.

The role and participation of the farmer is as central to addressing the problem. This will not be possible without addressing underlying aspects of the effectiveness of agriculture policy and institutions, its interface with farmers, trust in these institutions, why farmers no longer wish to continue farming as well as alternative meanings and approaches to sustainability in agriculture and food systems in the region. An understanding of their values, concerns and the prevalent societal norms that underlies behavioural patterns is vital-not in the least because the volumes of residue that can be accommodated by off-field options are a fraction of what is generated. They must be made equal partners in this endeavour as must other stakeholders including agri-extension agencies, civil society organisations, R&D institutions, entrepreneurs, equipment manufacturers and suppliers, aggregators.

A number of multi-stakeholder partnerships are rising to the challenge of addressing paddy residue burning and air pollution. What has emerged from these discussions is the need for alignment between the ministries dealing with agriculture, water resources, clean energy and health and a coordinated response to tackle this immensely complex problem. In all likelihood, a basket of options may be necessitated for developing solutions. There is also a growing trend of burning wheat residue of not only paddy but also wheat. As these fires engulf the nation, a lot will ride on the design and implementation of an appropriate programmes and policies for addressing crop residue burning.